Nemoria bistriaria
In 3 days ~10% in a week ~20%
Nemoria bistriaria, the red-fringed emerald or two-striped emerald, is a species of moth of the family Geometridae. It is found from New Brunswick to Florida, west to Central Coast of California, north to Ontario. The wingspan is about 22 mm. Adults are on wing from March to October in the south and from May to August in the north. There are at least two generations per year. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Great Smoky Mountains National Park | 🇺🇸 United States |
More parks will be added in future updates.
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Baltimore | 🇺🇸 United States | |
| 2 | Washington | 🇺🇸 United States | |
| 3 | Boston | 🇺🇸 United States | |
| 4 | New York City | 🇺🇸 United States | |
| 5 | Chicago | 🇺🇸 United States | |
| 6 | Toronto | 🇨🇦 Canada |
Rare
Under 5% of wildlife watchers report a Red-Fringed Emerald sighting in Boston on a given day, based on 10 verified sightings from GBIF citizen-science data. It is the 738th most-seen of the 1200 insects we can rate there. Over three days the chance rises to about 10%, and over a week to about 20%, if each day is a fresh chance.
May
In that month about 10% of wildlife watchers report a Red-Fringed Emerald in Boston on a given day, against under 5% in June to April, the lowest months.
Between midnight and 3 am
Across all the parks we cover, that three-hour window holds the most Red-Fringed Emerald sightings with a recorded time, and nearly all of them come between 6 pm and 6 am: it is mostly seen at night.
Among the best
Of the 6 cities where we can rate Red-Fringed Emerald sightings, Boston ranks 3rd at under 5%, level with the leaders once rounded. The best odds are in Baltimore (United States, under 5%) and Washington (United States, under 5%).
Same family: Geometridae
The closest relatives of the Red-Fringed Emerald that you can see in Boston (family Geometridae, Geometer Moths) are Pale Beauty (about 10%), Single-Dotted Wave (about 10%) and Winter Moth (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Red-Fringed Emerald is recorded against all the insects logged in Boston (10 verified sightings), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
